package com.lzw.bluetoothpractice.Utils;


import android.annotation.SuppressLint;
import android.content.Context;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;
import android.content.pm.PackageManager.NameNotFoundException;
import android.os.Build;
import android.os.Environment;
import android.os.Looper;
import android.os.StatFs;
import android.util.Log;
import android.widget.Toast;

import java.io.File;
import java.io.FileOutputStream;
import java.io.PrintWriter;
import java.io.StringWriter;
import java.io.Writer;
import java.lang.Thread.UncaughtExceptionHandler;
import java.lang.reflect.Field;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.HashMap;
import java.util.Locale;
import java.util.Map;

/**
 * UncaughtException处理类,当程序发生Uncaught异常的时候,有该类来接管程序,并记录发送错误报告.
 *
 * @author user
 */
@SuppressLint("SdCardPath")
public class CrashHandler implements UncaughtExceptionHandler {

    private static final String TAG = "CrashHandler";

    public final static long K = 1024;
    public final static long M = 1024 * 1024;
    // 外置存储卡默认预警临界值
    private static final long THRESHOLD_WARNING_SPACE = 100 * M;
    // 保存文件时所需的最小空间的默认值
    public static final long THRESHOLD_MIN_SPCAE = 60 * M;

    // CrashHandler 实例
    private static CrashHandler INSTANCE = new CrashHandler();

    // 程序的 Context 对象
    private Context mContext;

    // 系统默认的 UncaughtException 处理类
    private UncaughtExceptionHandler mDefaultHandler;

    // 用来存储设备信息和异常信息
    private static Map<String, String> infos = new HashMap<String, String>();

    // 用来显示Toast中的信息
    private static String error = "程序崩溃！！";

    // 用于格式化日期,作为日志文件名的一部分
    private static DateFormat formatter = new SimpleDateFormat("yyyy-MM-dd-HH-mm-ss", Locale.CHINA);

    /**
     * 保证只有一个 CrashHandler 实例
     */
    private CrashHandler() {
        //
    }

    /**
     * 获取 CrashHandler 实例 ,单例模式
     */
    public static CrashHandler getInstance() {
        return INSTANCE;
    }

    /**
     * 获取外置存储卡剩余空间
     *
     * @return
     */
    public static long getAvailableExternalSize(String directoryPath) {
        try {
            StatFs sf = new StatFs(directoryPath);
            long blockSize = sf.getBlockSize();
            long availCount = sf.getAvailableBlocks();
            long availCountByte = availCount * blockSize;
            return availCountByte;
        } catch (Exception e) {
            e.printStackTrace();
        }
        return 0;
    }

    /**
     * 判断外部存储是否存在，以及是否有足够空间保存指定类型的文件
     *
     * @param
     * @return false: 无存储卡或无空间可写, true: 表示ok
     */
    public static boolean hasEnoughSpaceForWrite(String directoryPath) {
        long residual = getAvailableExternalSize(directoryPath);
        if (residual < THRESHOLD_MIN_SPCAE) {
            return false;
        } else if (residual < THRESHOLD_WARNING_SPACE) {

        }

        return true;
    }

    /**
     * 初始化
     *
     * @param context
     */
    public void init(Context context) {
        mContext = context;

        // 获取系统默认的 UncaughtException 处理器
        mDefaultHandler = Thread.getDefaultUncaughtExceptionHandler();

        // 设置该 CrashHandler 为程序的默认处理器
        Thread.setDefaultUncaughtExceptionHandler(this);
    }

    /**
     * 当 UncaughtException 发生时会转入该函数来处理
     */
    @Override
    public void uncaughtException(Thread thread, Throwable ex) {
        if (!handleException(ex) && mDefaultHandler != null) {
            // 如果用户没有处理则让系统默认的异常处理器来处理
            mDefaultHandler.uncaughtException(thread, ex);
        } else {
            try {
                Thread.sleep(3000);
            } catch (InterruptedException e) {
                Log.e(TAG, "error : ", e);
            }

            // 退出程序
            android.os.Process.killProcess(android.os.Process.myPid());
            // mDefaultHandler.uncaughtException(thread, ex);
            System.exit(1);
        }
    }

    /**
     * 自定义错误处理，收集错误信息，发送错误报告等操作均在此完成
     *
     * @param ex
     * @return true：如果处理了该异常信息；否则返回 false
     */
    private boolean handleException(Throwable ex) {
        if (ex == null) {
            return false;
        }

        // 收集设备参数信息
        collectDeviceInfo(mContext);
        // 保存日志文件
        saveCrashInfo2File(ex);
        // 使用 Toast 来显示异常信息
        new Thread() {
            @Override
            public void run() {
                Looper.prepare();
                Toast.makeText(mContext, error, Toast.LENGTH_LONG).show();
                Looper.loop();
            }
        }.start();
        return true;
    }

    /**
     * 收集设备参数信息
     *
     * @param ctx
     */
    public static void collectDeviceInfo(Context ctx) {
        try {
            PackageManager pm = ctx.getPackageManager();
            PackageInfo pi = pm.getPackageInfo(ctx.getPackageName(),
                    PackageManager.GET_ACTIVITIES);

            if (pi != null) {
                String versionName = pi.versionName == null ? "null" : pi.versionName;
                String versionCode = pi.versionCode + "";
                infos.put("versionName", versionName);
                infos.put("versionCode", versionCode);
            }
        } catch (NameNotFoundException e) {
            Log.e(TAG, "an error occured when collect package info", e);
        }

        Field[] fields = Build.class.getDeclaredFields();
        for (Field field : fields) {
            try {
                field.setAccessible(true);
                infos.put(field.getName(), field.get(null).toString());
                Log.d(TAG, field.getName() + " : " + field.get(null));
            } catch (Exception e) {
                Log.e(TAG, "an error occured when collect crash info", e);
            }
        }
    }

    /**
     * 删除单个文件
     *
     * @param filePath 被删除文件的文件名
     * @return 文件删除成功返回true，否则返回false
     */
    public static boolean deleteFile(String filePath) {
        File file = new File(filePath);
        if (file.isFile() && file.exists()) {
            return file.delete();
        }
        return false;
    }

    /**
     * 删除文件夹下的文件
     *
     * @param filePath 被删除目录下文件的路径
     * @return 目录删除成功返回true，否则返回false
     */
    public static boolean deleteDirectory(String filePath) {
        boolean flag = false;

        //如果filePath不以文件分隔符结尾，自动添加文件分隔符
        if (!filePath.endsWith(File.separator)) {
            filePath = filePath + File.separator;
        }

        File dirFile = new File(filePath);
        if (!dirFile.exists() || !dirFile.isDirectory()) {
            return false;
        }

        flag = true;
        File[] files = dirFile.listFiles();

        //遍历删除文件夹下的所有文件(包括子目录)
        for (int i = 0; i < files.length; i++) {
            if (files[i].isFile()) {
                //删除子文件
                flag = deleteFile(files[i].getAbsolutePath());
                if (!flag) break;
            }
        }

        if (!flag) return false;

        return true;
    }

    /**
     * 保存错误信息到文件中 *
     *
     * @param ex
     * @return 返回文件名称, 便于将文件传送到服务器
     */
    public static String saveCrashInfo2File(Throwable ex) {
        StringBuffer sb = getTraceInfo(ex);

        for (Map.Entry<String, String> entry : infos.entrySet()) {
            String key = entry.getKey();
            String value = entry.getValue();
            sb.append(key + "=" + value + "\n");
        }

        Writer writer = new StringWriter();
        PrintWriter printWriter = new PrintWriter(writer);
        ex.printStackTrace(printWriter);
        Throwable cause = ex.getCause();
        while (cause != null) {
            cause.printStackTrace(printWriter);
            cause = cause.getCause();
        }
        printWriter.close();

        String result = writer.toString();
        sb.append(result);
        try {
            long timestamp = System.currentTimeMillis();
            String time = formatter.format(new Date());
            String fileName = "TLH-Crash-" + time + "-" + timestamp + ".log";

            if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) {
                String path = Environment.getExternalStorageDirectory() + "/crash/";
                File dir = new File(path);

                if (!dir.exists()) {
                    dir.mkdirs();
                } else if (!hasEnoughSpaceForWrite(path)) {
                    deleteDirectory(path);
                }

                FileOutputStream fos = new FileOutputStream(path + fileName);
                fos.write(sb.toString().getBytes());
                fos.close();
            }

            return fileName;
        } catch (Exception e) {
            Log.e(TAG, "an error occured while writing file...", e);
        }

        return null;
    }

    /**
     * 整理异常信息
     *
     * @param e
     * @return
     */
    public static StringBuffer getTraceInfo(Throwable e) {
        StringBuffer sb = new StringBuffer();

        Throwable ex = e.getCause() == null ? e : e.getCause();
        StackTraceElement[] stacks = ex.getStackTrace();
        for (int i = 0; i < stacks.length; i++) {
            sb.append("class: ").append(stacks[i].getClassName())
                    .append("; method: ").append(stacks[i].getMethodName())
                    .append("; line: ").append(stacks[i].getLineNumber())
                    .append(";  Exception: ").append(ex.toString() + "\n");
        }
        return sb;
    }
}